Marine creatures face the long arm of the scientific law as their "fingerprints" go on record

Abby Fusaro. Image: Gary Cranitch

By Angus Livingston

Thursday 21 May 2009

EVERY human being has fingerprints – a unique set of lines on our fingertips that can be used to put our identity beyond doubt. An inky finger pressed onto paper and our branding is revealed, providing an accurate and reliable method of identification.

That ability to consistently identify a human is something the Ocean Genome Legacy Foundation is trying to transfer to the marine arena.

No, they're not making polychaetes swim through ink or putting crab claws on an ID sheet. Instead, they're looking at their DNA to find a common sequence that is unique to each species.

Just as every human has fingers, so we know where to look to get fingerprints, a large number of marine organisms have a common DNA sequence in a predictable spot.

That sequence – cytochrome oxidase 1 – is the piece that allows scientists like Dr Abby Fusaro to definitively identify a sample as a particular marine organism.

"The idea is that it's unique per species. It's a quick molecular ID," she said.

Once a species has been identified and the CO1 ‘barcode' sequence confirmed, the information is stored in the Barcode of Life Database.

It then becomes available to scientists to search and use in their research.

Abby said the barcode allowed scientists to identify samples of larvae or determine if different-looking individuals were the same species or not.

Eventually the technology will allow for large quantities of genetic material to be collected and sampled en masse, however Abby said there were still some kinks to be worked out.

One of those kinks includes the fact some marine organisms can't be told apart by their CO1 sequence.

Some corals and sponges have shown this tendency, so Abby and the Ocean Genome Legacy Foundation are trying to find other consistent DNA sequences in those organisms' genetic makeup to correctly identify them.

Another issue is the technology used to amplify the CO1 sequences.

At the moment it still cannot identify every piece of DNA in a mass sample; however Abby said it was still useful to better understand the biodiversity of an area.

"We can get some estimate of diversity, but we know we're not getting everything," she said.

While there are still issues to sort out, there is still a lot of collecting and barcoding to be done.

Abby has been working at Ningaloo to collect samples of the organisms so she can identify them back in the lab.

Eventually, scientists will be able to ‘fingerprint' every sample they collect, giving them a much better understanding of the biodiversity of the world's oceans.